People with close family and social ties have 50 per cent more chances of living longer than those living isolated lives without friends, families or colleagues, says a new global study.

People with close family and social ties have 50 per cent more chances of living longer than those living isolated lives without friends, families or colleagues, says a new global study.

Isolation is as harmful as smoking 15 cigarettes a day, being alcoholic or obese, says the study led by Julianne Holt-Lunstad, an associate professor of psychology at Brigham Young University in Utah state.

The report, which is a compilation of 148 studies that followed 308,849 people — with an average age of 64 — for about seven and a half years, says that those with strong personal ties lived about four years longer than those with weaker social ties.